Reef nutrition

Corals losing color. Can't figure out why.

Enderturtle

Enderturtle

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I have a 16" deep 40 gallon breeder with two Kessil 350W's on top. The Kessils are attached using a gooseneck allowing them to be 8 inches from the top of the tank. Total height from the kessil to the bottom of the tank is 24 inches Tank is only 5 months old but fully cycled. Has been fallow for 1.25 months for ich treatment.

Kessil settings are 40% Blue and 15% White light for 8 hours a day.

This torch coral I got about a month ago has decreased significantly in color. It's tentacles are not green anymore but the mouth is still green. He is sitting at the bottom of the tank. Tentacles are shorter than usual. This coral came from a shallow frag tank sitting under Radian Gen 3 lights (almost no white light)

My Hammer coral was doing awesome for a while and then nose dived. I had him half way up the tank in full light. He reacted great for about a month and then shrivled to nothing. I put him in the shade and he recovered but not to his original extent. The hammer's tentacles are shaped like a torch now. They use to be hammer shaped and his tentacles do not appear to be fully extended. He is sitting in full light approximately 2 inches off the bottom.

My Red and Green blasto was vibrant red when I got him and is now a dull red. He was on the sandbed and i moved him 2 inches up. He expelled zoxanthelle so I put him in the shade where he's been for the past month and has not regained his vibrant color.

Also my I have Montipora undata and Montipora cap at the highest point in the tank and the undata has browned out, while the capricornus has dulled in color, turning a brownish red. The montis turned to this color during the dip (Revive dip for 10 minutes) and have not recovered. They have been in the tanks for at least 2 months.

Tank Parameters are:

SG: 1.024
pH: 8.0
Calcium: Ranges from 400-450
Alkalinity: Ranges from 8 to 10
Nitrates: Close to 0
Phosphates: Close to 0

Too much light? Not enough light? Calcium and alkalinity swing slightly but within the acceptable ranges.

Overview of Tank
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Picture of Torch when I got it.
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Picture of Torch Now
IMG_9233 by buyandsellstuffmike, on Flickr


Picture of Hammer at Beginning



Picture of Hammer Now


Picture of Red-Green Blastomussa




Zoanthids are growing fine. I have a skimmer that keeps my tank very clean. Though I don't think the tank is too clean for coral growth because I have minor hair algae and chaeto growth in my sump.
 
PH is slightly on the low side, my corals seem to like PH to be >8.0 but probably not the root cause.
How long have the corals been under the light at that intensity? it may be time to crank your lighting up slightly and watching how the corals react.

Another thing to look into is test kits, sometimes if you're getting a false reading on nitrates or phosphate the problem could be right there so if you have other test kits to compare I would do this first.
 
If the lighting type and intensity have been constant, and the corals now have little color, it is likely that the tank is too 'clean' since you left it fallow for 1-1/2 months (I'm assuming that you didn't 'ghost feed' the tank during this time). I also don't see much in the way of algae in your pics, so that's another clue (along with a '0' reading of NO3 and PO4). Are you getting any algae film on the glass after a few days, or do the viewing walls stay clear for a week? Try some target feeding for the SPS and the LPS 2-3x week and see if you see color improvements in 2-3 weeks.
 
It's possible its too clean but I am getting good algae growth in my sump which is being lit by a CFL bulb.

The display tank does get diatoms and bacterial on the glass which I scrape off. I target feed my acans, dendro, and other corals almost every day. Tons of copepods.'


Here are my current hypotheses:
1) kessils are too intense for corals
2) I often feed at night and that involves turning on the lights after they've been turned off. Sometimes I turn them on in the morning for like 10 minutes. Feeding times will require approximately 10 minutes too and then I turn them off.
3) I use RO water instead of RODI water. I've tested the water and it has 0 phosphates and 0 copper. The RO water is filtered using RO, 2 rounds of carbon, and UV.
 
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Hmmm, well there goes the 'low nutrient' hypothesis :)

Two of those lights will put out some good PUR at your settings even if PAR is not all that high. Have you found any threads with similar Kessil lighting setups where PAR is referenced? Having more blue than white intensity is typically preferred, so you're okay there. The LPS that you have are fairly low-light corals (Torches, Hammers), so they *may* be getting a bit too much light, but without a PAR meter it's difficult to know for sure. Blastos like even lower light than Euphyllia, so that's likely why it stressed when you tried to move it up.

Hopefully someone using your Kessil model will have some input for you.
 
If it were me, I would try to get the specific gravity to 1.025, pH up to 8.1/8.2, and alkalinity no less than 9.0. Also, it would be great to get your PAR reading to get a sense of what's going on at the different levels of your tank. My gut guess is that the corals are getting too much light. How far are the Kessils from the water surface?
 
8 inches from the water surface which is the highest the goosenecks can go.

Maybe i could turn down the light intensity and slowly work up? But how will I know if my corals arent getting enough light?
 
I was going to guess it could be not enough light, but like you pointed out its been the same. Could still be the light if those corals were just added to the tank when you took those pictures. Meaning they were healthy from the original tank.

I'm noticing the same thing happening to my zoas. Ive been turning down the light intensity because its been so hot....and now their colors look bland. I just started to turn it back up today.
 
Lights: LED's tend to roast corals more often than not, so I'd vote that the corals are probably getting too much light. You might get better light spread if you move your lights further apart. You can tell in the pic that you have an area of really bright light in the center of the tank and the edges are a bit darker. It looks like the torch is in an area of high light. I'd also try turning the lights down a bit every week and see how things go.

Nutrients: The torch looks like it's turning brown, which tends to be a high nutrient issue. What are you using to test nitrate and phosphates? Since you say you have algae growing in the sump, I'd also wager that higher phosphates might be contributing to the loss of color.
 
Enderturtle said:
Hmmm using api test kit but have also used phosphate test kit by elos. Both measured 0.
Click to expand...

You should just throw the API phosphate test in the trash. It's not really useful for measuring anything in a reef tank. The lowest it reads is .25, you want readings in the .03 +/- range.

The elos test should be giving you accurate readings, but since it's telling you "0", and you have algae growth, I'm suspecting it's not right.

Are you running anything for phosphate reduction?
 
Well i grow chaeto in the fuge and the hair algae in my fuge is minor so I take it phosphates arent that high. I feed very little as there are no fish in the tank. I feel its the lights. Maybe ill try 0% white for a while and crank blue down to 25%.

The chaeto has grown very slowly. Probably increased in size by about 15% since i got it 2 months ago. Hair algae just started coming in and only growing on a rock in fuge
 
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I think your lights are to strong. LEDs can be deceiving to your eyes. What looks dim to your eyes can still provide lots of light in your tank.
 
Some other things worth mentioning. I have radio dragon eye zoas and ring of fire zoas halfway up the tank. They are loving the light. Duncan about 3/4 up tank hes doing fine too.
 
I have 6 Kessil's over 3 tanks. I learned with my first set of 2 that they are very powerful,and can easily burn corals. My guess is that since your tank is only 16in deep that the corals are getting too much light. The corals we are talking about do not need high intensity light so if it was me I would move them to the bottom and reduce the wattage, it would be good if you could measure the watts with a "kill a watt" meter. I would start with 20 watts of white and blue. This would give you about 15000k and a total of 40 watts. If the corals stabilize I would then increase the wattage by 5 watts each month. With the corals you have I would not increase the watts over a total of 60. And this can be any combination of white and blue.
 
The Kessil 350's are 90 watts total. They won't release information on their chips, but let's assume 40% is white and 60% is blue. That's 54 watts of blue total x 20% = approx. 11 watts each fixture. My sump has a 14 watt PAR 30 on it that runs 10 hours a day and keeps everything colored well, so I'd say you are probably low now.

I'd also recomend a more gradual change too. It takes time to corals to adjust to different lighting, and making drastic changes just stresses them out. Only bad things happen quickly in this hobby...

FWIW, you may want to reconsider the all blue approach too. Again, Kessil won't release information on their chips, but all indications are that the Violet and "UV" LED's are looped in whith their blue spectrum. As you crank up the blue you are also probably cranking up the Violet/UV, which can bleach out corals.
 
If you want to borrow my wattage meter your welcome to come over and get it. I live in Oakland. You certainly need more than 20 percent blue and zero white. Don't worry about how much blue and white you have. John at Kessil told us that they made the spectrum at any setting to be sufficent to grow coral. The only veritable is how many watts you dial up. If you don't want the light meter I would move the control knob about a a quarter for blue and white and then each month increase it as long as the corals are looking good. I want to emphasize that at 16 in. Your tank is very shallow for led lights.
 
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